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It is shown that a Weakly Interacting Massive dark matter Particle (WIMP) interpretation for the positron excess observed in a variety of experiments, HEAT, PAMELA, and AMS-02, is highly constrained by the Fermi/LAT observations of dwarf galaxies. In particular, this paper has focused on the annihilation channels that best fit the current AMS-02 data (Boudaud et al., 2014). The Fermi satellite has surveyed the $gamma$-ray sky, and its observations of dwarf satellites are used to place strong bounds on the annihilation of WIMPs into a variety of channels. For the single channel case, we find that dark matter annihilation into {$bbar{b}$, $e^+e^-$, $mu^+mu^-$, $tau^+tau^-$, 4-$e$, or 4-$tau$} is ruled out as an explanation of the AMS positron excess (here $b$ quarks are a proxy for all quarks, gauge and Higgs bosons). In addition, we find that the Fermi/LAT 2$sigma$ upper limits, assuming the best-fit AMS-02 branching ratios, exclude multichannel combinations into $bbar{b}$ and leptons. The tension between the results might relax if the branching ratios are allowed to deviate from their best-fit values, though a substantial change would be required. Of all the channels we considered, the only viable channel that survives the Fermi/LAT constraint and produces a good fit to the AMS-02 data is annihilation (via a mediator) to 4-$mu$, or mainly to 4-$mu$ in the case of multichannel combinations.
A convex polyhedron $P$ is $k$-equiprojective if all of its orthogonal projections, i.e., shadows, except those parallel to the faces of $P$ are $k$-gon for some fixed value of $k$. Since 1968, it is an open problem to construct all equiprojective po lyhedra. Recently, Hasan and Lubiw [CGTA 40(2):148-155, 2008] have given a characterization of equiprojective polyhedra. Based on their characterization, in this paper we discover some new equiprojective polyhedra by cutting and gluing existing polyhedra.
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